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51. 5C12: survey near the North Galactic Pole
ID:
ivo://CDS.VizieR/J/MNRAS/200/747
Title:
5C12: survey near the North Galactic Pole
Short Name:
J/MNRAS/200/747
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains a deep survey (5C12) of a region close to the North Galactic Pole carried out with the Cambridge One-Mile Telescope at 408 MHz (HPBW 80"x139") and at 1407 MHz (HPBW 23"x40"). The flux densities are on the KPW scale (Kellermann et al. 1969ApJ...157....1K), and were based on 3C48, 3C147 and 3C295. This part of the survey contains 321 sources with apparent flux densities brighter than 9 mJy at 408 MHz or 1.4 mJy at 1407 MHz.
52. 10C survey of radio sources at 15.7GHz
ID:
ivo://CDS.VizieR/J/MNRAS/415/2708
Title:
10C survey of radio sources at 15.7GHz
Short Name:
J/MNRAS/415/2708
Date:
21 Oct 2021
Publisher:
CDS
Description:
In a previous paper (Paper I, Franzen et al., 2011MNRAS.415.2699F), the observational, mapping and source-extraction techniques used for the Tenth Cambridge (10C) Survey of Radio Sources were described. Here, the first results from the survey, carried out using the Arcminute Microkelvin Imager Large Array (LA) at an observing frequency of 15.7GHz, are presented. The survey fields cover an area of ~27deg^2^ to a flux-density completeness of 1mJy. Results for some deeper areas, covering ~12deg^2^, wholly contained within the total areas and complete to 0.5mJy, are also presented. The completeness for both areas is estimated to be at least 93 per cent. The 10C survey is the deepest radio survey of any significant extent (>~0.2deg^2^) above 1.4GHz.
53. Deep 15GHz survey (9C continued)
ID:
ivo://CDS.VizieR/J/MNRAS/404/1005
Title:
Deep 15GHz survey (9C continued)
Short Name:
J/MNRAS/404/1005
Date:
21 Oct 2021
Publisher:
CDS
Description:
The 9C survey of radio sources with the Ryle Telescope at 15.2GHz was set up to survey the fields of the cosmic microwave background telescope, the Very Small Array. In our first paper we described three regions of the survey, constituting a total area of to a completeness limit of ~25mJy. Here we present results from series of deeper regions, amounting to an area of 115deg^2^ complete to ~10mJy and of 29deg^2^ complete to ~5.5mJy. The compound source catalogue contains a total of 643 sources.
54. DG Tau B ALMA observations
ID:
ivo://CDS.VizieR/J/A+A/636/A65
Title:
DG Tau B ALMA observations
Short Name:
J/A+A/636/A65
Date:
21 Oct 2021
Publisher:
CDS
Description:
The chemical composition of planets is determined by the distribution of the various molecular species in the protoplanetary disk at the time of their formation. To date, only a handful of disks have been imaged in multiple spectral lines with high spatial resolution. As part of a small campaign devoted to the chemical characterization of disk-outflow sources in Taurus, we report on new ALMA Band 6 (1.3mm) observations with 0.15" (20au) resolution toward the embedded young star DG Tau B. Images of the continuum emission reveals a dust disk with rings and, putatively, a leading spiral arm. The disk, as well as the prominent outflow cavities, are detected in CO, H_2_CO, CS, and CN; instead, they remain undetected in SO_2_, HDO, and CH_3_OH. From the absorption of the back-side outflow, we inferred that the disk emission is optically thick in the inner 50au. This morphology explains why no line emission is detected from this inner region and poses some limitations toward the calculation of the dust mass and the characterization of the inner gaseous disk. The H_2_CO and CS emission from the inner 200au is mostly from the disk, and their morphology is very similar. The CN emission significantly differs from the other two molecules as it is observed only beyond 150au. This ring-like morphology is consistent with previous observations and the predictions of thermochemical disk models. Finally, we constrained the disk-integrated column density of all molecules. In particular, we found that the CH_3_OH/H_2_CO ratio must be smaller than ~2, making the methanol non-detection still consistent with the only such ratio available from the literature (1.27 in TW Hya).
55. DRAO ELAIS N1 catalog
ID:
ivo://CDS.VizieR/J/ApJ/714/1689
Title:
DRAO ELAIS N1 catalog
Short Name:
J/ApJ/714/1689
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of deep polarization imaging at 1.4GHz with the Dominion Radio Astrophysical Observatory as part of the DRAO Planck Deep Fields project. This deep extragalactic field covers 15.16deg^2^ centered at RA(J2000)=16:14 and DE(J2000)=54:56, has an angular resolution of 42"x62" at the field center, and reaches a sensitivity of 55uJy/beam in Stokes I and 45uJy/beam in Stokes Q and U. We detect 958 radio sources in Stokes I of which 136 are detected in polarization. We present the Euclidean-normalized polarized differential source counts down to 400uJy. These counts indicate that sources have a higher degree of fractional polarization at fainter Stokes I flux density levels than for brighter sources, confirming an earlier result. We find that the majority of our polarized sources are steep-spectrum objects with a mean spectral index of -0.77, and there is no correlation between fractional polarization and spectral index. We also matched deep field sources to counterparts in the Faint Images of the Radio Sky at Twenty Centimeters catalog. Of the polarized sources, 77% show structure at the arcsecond scale whereas only 38% of the sources with no detectable polarization show such structure. The median fractional polarization for resolved sources is 6.8%, while it is 4.4% for compact objects. The polarized radio sources in our deep field are predominantly those sources which are resolved and show the highest degrees of fractional polarization, indicating that the lobe dominated structure may be the source of the highly polarized sources. These resolved radio galaxies dominate the polarized source counts at P_0_=(Q^2^+U^2^)^0.5^<3mJy.
56. DRAO Penticton P-survey Database
ID:
ivo://CDS.VizieR/VIII/55
Title:
DRAO Penticton P-survey Database
Short Name:
VIII/55
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains 1692 radio sources observed with the Penticton synthesis telescope at 408 MHz and at 1420 MHz. The catalog is comprised of sources detected in the P-surveys 1P through 9P, 12P through 15P, and 20P through 27P (see the "References" section below). The database was provided by R.Roger & C.R.Purton in May 1990 and an update of the data with further P-surveys is currently in progress.
57. E and SO galaxies survey at 2.7 and 5.0 GHz
ID:
ivo://CDS.VizieR/J/AJ/89/53
Title:
E and SO galaxies survey at 2.7 and 5.0 GHz
Short Name:
J/AJ/89/53
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents results from a continuum radio survey of a complete sample of 248 southern E and S0 galaxies. All the galaxies were observed at 2.7GHz (11cm) with the Parkes radio telescope, and those detected were reobserved at 5.0 GHz (6 cm). Thirty-seven galaxies were detected above a level of 25-30mJy, and a consideration of the background source density at 2.7GHz indicates that no more than two or three of these detections are due to background sources.
58. Extended radio emission in MOJAVE blazars
ID:
ivo://CDS.VizieR/J/ApJ/710/764
Title:
Extended radio emission in MOJAVE blazars
Short Name:
J/ApJ/710/764
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a study on the kiloparsec-scale radio emission in the complete flux density limited MOJAVE sample, comprising 135 radio-loud active galactic nuclei. New 1.4GHz Very Large Array (VLA) radio images of six quasars and previously unpublished images of 21 blazars are presented, along with an analysis of the high-resolution (VLA A-array) 1.4GHz emission for the entire sample. While extended emission is detected in the majority of the sources, about 7% of the sources exhibit only radio core emission. We expect more sensitive radio observations, however, to detect faint emission in these sources, as we have detected in the erstwhile "core-only" source, 1548+056. The kiloparsec-scale radio morphology varies widely across the sample. Many BL Lac objects exhibit extended radio power and kiloparsec-scale morphology typical of powerful FRII jets, while a substantial number of quasars possess radio powers intermediate between FRIs and FRIIs.
59. Extended sources in SCORPIO at 2.1GHz
ID:
ivo://CDS.VizieR/J/MNRAS/490/5063
Title:
Extended sources in SCORPIO at 2.1GHz
Short Name:
J/MNRAS/490/5063
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of a large sample of extended radio sources in the Stellar Continuum Originating from Radio Physics In Ourgalaxy (SCORPIO) field, observed and resolved by the Australia Telescope Compact Array. SCORPIO, a pathfinder project for addressing the early operations of the Australia SKA Pathfinder, is a survey of ~5 square degrees between 1.4 and 3.1GHz, centred at l=343.5{deg}, b=0.75{deg}, and with an angular resolution of about 10 arcsec. It is aimed at understanding the scientific and technical challenges to be faced by future Galactic surveys. With a mean sensitivity around 100uJy/beam and the possibility to recover angular scales at least up to 4 arcmin, we extracted 99 extended sources, 35 of them detected for the first time. Among the 64 known sources 55 had at least a tentative classification in literature. Studying the radio morphology and comparing the radio emission with infrared we propose as candidates six new HII regions, two new planetary nebulae, two new luminous blue variable or Wolf-Rayet stars, and three new supernova remnants. This study provides an overview of the potentiality of future radio surveys in terms of Galactic source extraction and characterization and a discussion on the difficulty to reduce and analyse interferometric data on the Galactic plane.
60. Extragalactic MHz Peaked Sources at mas scales
ID:
ivo://CDS.VizieR/J/A+A/628/A56
Title:
Extragalactic MHz Peaked Sources at mas scales
Short Name:
J/A+A/628/A56
Date:
21 Oct 2021
Publisher:
CDS
Description:
Extragalactic peaked-spectrum radio sources are thought to be the progenitors of larger, radio-loud active galactic nuclei (AGN). Synchrotron self-absorption (SSA) has often been identified as the cause of their spectral peak. The identification of new megahertz-peaked spectrum sources from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey provides an opportunity to test how radio sources with spectral peaks below 1GHz fit within this evolutionary picture. We observed six peaked-spectrum sources selected from the GLEAM survey, three that have spectral characteristics which violate SSA and three that have spectral peaks below 230MHz, with the Very Long Baseline Array at 1.55 and 4.96 GHz. We present milliarcsecond resolution images of each source and constrain their morphology, linear size, luminosity, and magnetic field strength. Of the sources that are resolved by our study, the sources that violate SSA appear to be compact doubles, while the sources with peak frequencies below 230MHz have core-jet features. We find that all of our sources are smaller than expected from SSA by factors of >~20. We also find that component magnetic field strengths calculated from SSA are likely inaccurate, differing by factors of >~5 from equipartition estimates. The calculated equipartition magnetic field strengths more closely resemble estimates from previously studied gigahertz-peaked spectrum sources. Exploring a model of the interaction between jets and the interstellar medium, we demonstrate that free-free absorption (FFA) can accurately describe the linear sizes and peak frequencies of our sources. Our findings support the theory that there is a fraction of peaked-spectrum sources whose spectral peaks are best modelled by FFA, implying our understanding of the early stages of radio AGN is incomplete.

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